Heat dissipation module and projection apparatus

ABSTRACT

A heat dissipation module and a projection apparatus are provided. The heat dissipation module dissipates the heat generated by a plurality of heating elements, includes a heat pipe, a heat dissipation plate, a first and a second heat dissipation fins. The heat pipe includes a first portion of the heat pipe passes through the first heat dissipation fin and a second portion of the heat pipe passes through the second heat dissipation fin and a third portion connected with the first and the second portions. The third portion of the heat pipe and the heating elements are connected to the heat dissipation plate. The heat generated by the heating elements is dissipated by the heat dissipation plate, the first and the second heat dissipation fins through thermal conduction method and thermal convection method. The invention saves accommodating space in the projection apparatus and has an efficient heat dissipation effect.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the priority benefit of China application serialno. 201821460990.7, filed on Sep. 7, 2018. The entirety of theabove-mentioned patent application is hereby incorporated by referenceherein and made a part of this specification.

BACKGROUND Field of the Invention

The invention relates a heat dissipation module and a projectionapparatus and more particularly, to a heat dissipation module with anefficient heat dissipation effect and a projection apparatus using theheat dissipation module.

Description of Related Art

In general, the primary heat sources are a light source and a lightvalve in a projection apparatus. In a conventional projection apparatus,a heat transfer system of a heat dissipation device, the heat sourcesare connected to heat sinks respectively for heat dissipation. However,in this method the entire system layout of the projection apparatus maybe dispersed, in such a way that more air guiding structures would berequired for solving an airflow issue. Moreover, an airflow volume ofthe entire system of the projection apparatus is also reduced, therebyreducing the heat dissipation capability of the projection apparatus.

The “Description of Related Art” section is only intended for enhancingunderstanding of the invention and therefore the content disclosed inthe “Description of Related Art” section may contain information thatdoes not form the related art already known to people skilled in theart. The disclosure in the “Description of Related Art” section does notmean that the content or the issues addressed by one or more embodimentsof the invention are already previously known or recognized by peopleskilled in the art.

The information disclosed in this Background section is only forenhancement of understanding of the background of the describedtechnology and therefore it may contain information that does not formthe prior art that is already known to a person of ordinary skill in theart. Further, the information disclosed in the Background section doesnot mean that one or more problems to be resolved by one or moreembodiments of the invention were acknowledged by a person of ordinaryskill in the art.

SUMMARY OF THE INVENTION

The invention provides a heat dissipation module with an efficient heatdissipation effect.

The invention further provides a projection apparatus including theaforementioned heat dissipation module, to reduce the space consumptionin the projection apparatus and have an efficient heat dissipationeffect.

Other features and advantages of the invention can be further understoodby the technical features disclosed in the invention.

To achieve one, part, or all of the objectives aforementioned or otherobjectives, a heat dissipation module of an embodiment of the inventionfor dissipating heat from a plurality of heating elements, and includesa heat pipe, a dissipation plate, a first heat dissipation fin and asecond heat dissipation fin. The heat pipe includes a first portion, asecond portion and a third portion connected with the first and thesecond portions. The first portion and the second portion are disposedin parallel to each other. The third portion of the heat pipe and theheating elements are connected to the heat dissipation plate. The firstportion of the heat pipe passes through the first heat dissipation fin.The second portion of the heat pipe passes through the second heatdissipation fin. The heat generated by the heating elements isdissipated by the heat dissipation plate, the first heat dissipation finand the second heat dissipation fin through a thermal conduction methodand a thermal convection method.

A projection apparatus provided by another embodiment of the inventionincludes a chassis, an optical engine, a projection lens and a heatdissipation module. The chassis has an air inlet and an air outlet. Theoptical engine is disposed inside the chassis and includes a pluralityof heating elements. The projection lens is disposed inside the chassisand connected with the optical engine. The heat dissipation module isdisposed inside the chassis, and includes a heat pipe, a dissipationplate, a first heat dissipation fin and a second heat dissipation fin.The heat pipe includes a first portion, a second portion and a thirdportion connected with the first and the second portions. The firstportion and the second portion are disposed in parallel to each other.The third portion of the heat pipe and the heating elements areconnected to the heat dissipation plate. The first portion of the heatpipe passes through the first heat dissipation fin. The second portionof the heat pipe passes through the second heat dissipation fin. Theheat generated by the heating elements is dissipated by the heatdissipation plate, the first heat dissipation fin and the second heatdissipation fin through a thermal conduction method and a thermalconvection method.

Based on the above, the embodiments of the invention achieve at leastone of the following advantages or effects. In this design of the heatdissipation module of the invention, the heat generated by the heatingelements which are disposed on the heat dissipation plate is dissipatedby a thermal conduction method and a thermal convection method and theheating elements relatively adjacent to the first portion of the heatpipe can also directly dissipated in a thermal convection method. Inother words, the design of the heat dissipation module of the inventionprovides one more heat dissipation method of thermal convection, so asto achieve an efficient heat dissipation effect. Moreover, theprojection apparatus using the heat dissipation module of the invention,can achieve an efficient dissipation effect, in addition it caneffectively reduce the space consumption in the projection apparatus andreduce volume and noise of the projection apparatus because all theheating elements are disposed on the heat dissipation plate, which areintegrated as one heat source.

Other objectives, features and advantages of the invention will befurther understood from the further technological features disclosed bythe embodiments of the invention where there are shown and describedpreferred embodiments of this invention, simply by way of illustrationof modes best suited to carry out the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings are included to provide a furtherunderstanding of the invention, and are incorporated in and constitute apart of this specification. The drawings illustrate embodiments of theinvention and, together with the description, serve to explain theprinciples of the invention.

FIG. 1 is a schematic diagram of a projection apparatus according to anembodiment of the invention.

FIG. 2 is a schematic diagram of a heat dissipation module of theprojection apparatus depicted in FIG. 1.

DESCRIPTION OF EMBODIMENTS

In the following detailed description of the preferred embodiments,reference is made to the accompanying drawings which form a part hereof,and in which are shown by way of illustration specific embodiments inwhich the invention may be practiced. In this regard, directionalterminology, such as “top,” “bottom,” “front,” “back,” etc., is usedwith reference to the orientation of the Figure(s) being described. Thecomponents of the present invention can be positioned in a number ofdifferent orientations. As such, the directional terminology is used forpurposes of illustration and is in no way limiting. On the other hand,the drawings are only schematic and the sizes of components may beexaggerated for clarity. It is to be understood that other embodimentsmay be utilized and structural changes may be made without departingfrom the scope of the present invention. Also, it is to be understoodthat the phraseology and terminology used herein are for the purpose ofdescription and should not be regarded as limiting. The use of“including,” “comprising,” or “having” and variations thereof herein ismeant to encompass the items listed thereafter and equivalents thereofas well as additional items. Unless limited otherwise, the terms“connected,” “coupled,” and “mounted” and variations thereof herein areused broadly and encompass direct and indirect connections, couplings,and mountings. Similarly, the terms “facing,” “faces” and variationsthereof herein are used broadly and encompass direct and indirectfacing, and “adjacent to” and variations thereof herein are used broadlyand encompass directly and indirectly “adjacent to”. Therefore, thedescription of “A” component facing “B” component herein may contain thesituations that “A” component directly faces “B” component or one ormore additional components are between “A” component and “B” component.Also, the description of “A” component “adjacent to” “B” componentherein may contain the situations that “A” component is directly“adjacent to” “B” component or one or more additional components arebetween “A” component and “B” component. The terms used herein such as“above,” “below,” “front,” “back,” “left,” and “right” are for thepurpose of describing directions in the figures only. Accordingly, thedrawings and descriptions will be regarded as illustrative in nature andnot as restrictive.

FIG. 1 is a schematic diagram of a projection apparatus according to anembodiment of the invention. FIG. 2 is a schematic diagram of a heatdissipation module of the projection apparatus depicted in FIG. 1. Itshould be mentioned that for clarity and descriptive convenience, a partof the elements (e.g., a part of a chassis is omitted, and a part of thechassis is represented by dashed lines. Referring to FIG. 1 and FIG. 2,in the embodiment, a projection apparatus includes a chassis 100, anoptical engine 200, a projection lens 300 and a heat dissipation module400. An air inlet 102 is provided at a side of the chassis 100, and anair outlet 104 is provided at the other side of the chassis 100, whereinthe air inlet 102 and the air outlet 104 are respectively located at twoopposite sides of the chassis 100. The optical engine 200 is disposedinside the chassis 100 and includes a plurality of heating elements 210,220, 230 and 240, wherein the heating elements 220, 230 and 240 include,for example, a plurality of light sources employed to emit anillumination beam, and the heating element 210 which is located on atransmission path of the illuminating beam and capable of converting theilluminating beam to an image beam is, for example, a light valve. Inthis case, the light valve 210 is a light modulation device, forexample, a digital micromirror device (DMD), the invention is notlimited thereto. In other embodiments, the light modulation device mayalso be a reflective liquid crystal on silicon (LCOS) or a transparentliquid crystal panel. The light sources are, for example, solid-stateillumination sources, such as light emitting diodes (LED) or laserdiodes. In this case, the light sources which include a red LED 220, agreen LED 230 and a blue LED 240 are taken as an example fordescription. The projection lens 300 is disposed inside the chassis 100,connected with the optical engine 200 and employed to project the imagebeam out of the chassis 100. As illustrated in FIG. 1, an air enteringdirection D1 of the air inlet 102 and an air exiting direction D2 of theair outlet 104 of the chassis 100 are not in parallel to a projectiondirection D3 of the projection lens 300. For example, the air enteringdirection D1 of the air inlet 102 and the air exiting direction D2 ofthe air outlet 104 of the chassis 100 are in perpendicular to theprojection direction D3 of the projection lens 300, the invention is notlimited thereto. The air entering direction D1 and the air exitingdirection D2 are defined as flowing directions of a cold airflow.

Referring again to FIG. 1 and FIG. 2, the heat dissipation module 400 ofthe embodiment is disposed inside the chassis 100 and includes a heatpipe 410, a dissipation plate 420, a first heat dissipation fin 430 anda second heat dissipation fin 440. The heat pipe 410 includes a firstportion 412, a second portion 414 and a third portion 416 connected withthe first portion 412 and the second portion 414, wherein the firstportion 412 and the second portion 414 are disposed in parallel to eachother. In this case, the heat pipe 410 is embodied in a U-shape, and thefirst portion 412 and the second portion 414 are disposed symmetricallyto each other. Additionally, a length of the second portion 414 is equalto a length of the first portion 412, but the invention is not limitedthereto. In other embodiments, the length of the second portion 414 maybe greater than the length of the first portion 412, so as to meet asize of the second heat dissipation fin 440. The third portion 416 ofthe heat pipe 410 is connected with the heat dissipation plate 420. Thethird portion 416 of the heat pipe 410 and the heating elements 210,220, 230 and 240 are located on the heat dissipation plate 420. Theheating elements 210, 220, 230 and 240 are connected with the heatdissipation plate 420. The third portion 416 of the heat pipe 410includes a contact portion 416 a, a first connection portion 416 b and asecond connection portion 416 c. The contact portion 416 a contacts theheat dissipation plate 420 and is connected with the first connectionportion 416 b and the second connection portion 416 c, wherein adiameter of the contact portion 416 a is greater than a diameter of thefirst connection portion 416 b and greater than a pipe diameter of thesecond connection portion 416 c, thereby increasing a heat dissipationarea to improve a heat dissipation efficiency. The first connectionportion 416 b is connected with the first portion 412 and the contactportion 416 a of the heat pipe 410, and the second connection portion416 c is connected with the second portion 414 and the contact portion416 a of the heat pipe 410. The first portion 412 of the heat pipe 410passes through the first heat dissipation fin 430, and the secondportion 414 of the heat pipe 410 passes through the second heatdissipation fin 440. The heating elements 220, 230 and 240 are disposedat a side of the heat dissipation plate 420 and adjacent to the secondportion 414 of the heat pipe 410, the heating element 210 is disposed atthe other side of the heat dissipation plate 420 and adjacent to thefirst portion 412 of the heat pipe 410.

It is to be mentioned that the heat pipe 410 is a hollow pipe and madeof metal, for example, copper. The heat pipe 410 is internally filledwith a cooling liquid, for example, water, and the pipe wall has acapillary structure or added with a porous material for returning thecooling liquid back to a heating end through an action of capillaryforce. The heat pipe 410 is adapted to transfer the heat from the heatdissipation plate 420. The U-shaped heat pipe 410 features in the firstportion of the heat pipe 410 passing through the first heat dissipationfin 430 and the second portion 414 of the heat pipe 410 passing throughthe second heat dissipation fin 440. Specifically, a length L2 of thesecond heat dissipation fin 440 along an extension direction E2 of thesecond portion 414 is greater than a length L1 of the first heatdissipation fin 430 along an extension direction E1 of the first portion412. Namely, the length L2 of the second heat dissipation fin 440 isgreater than the length L1 of the first heat dissipation fin 430.Because the length of the second portion 414 of the heat pipe 410 isequal to or slightly greater than the length of the first portion 412,this means that a part of the first portion 412 of the heat pipe 410 isnot blocked by the first heat dissipation fin 430. In this case, theextension direction E1 of the first portion 412 and the extensiondirection E2 of the second portion 414 are both perpendicular to the airentering direction D1 of the air inlet 102 and the air existingdirection of the air outlet 104. As illustrated in FIG. 1, the firstheat dissipation fin 430 does not block the heat dissipation plate 420in the air entering direction D1, and thus, when the cold airflowflowing through the air inlet 102 enters the chassis 100, the heatgenerated by the heating element 210 among the heating elements 210,220, 230 and 240 may be dissipated to the outside in a direct thermalconvection method as well as a thermal conduction and a thermalconvection method. In other words, besides the heat generated by theheating elements 210, 220, 230 and 240 may be dissipated through thermalconduction provided by the heat dissipation plate 420 plus thermalconvection provided by the first heat dissipation fin 430 and the secondheat dissipation fin 440, the heating element 210 which is relativelyadjacent to the first portion 412 of the heat pipe 410 may also becooled directly through thermal convection provided by a part of thecold airflow which enters through the air inlet 102 without flowingthrough the first heat dissipation fin 430. Moreover, the design of theheat dissipation module 400 of the embodiment provides one more heatdissipation path of thermal convection to achieve an efficient heatdissipation effect. In addition, as the heating element 210 (i.e., thelight valve) is not heat-resistant, the heating element 210 is cooleddirectly by the cold airflow, thereby effectively increasing thelifespan and reliability.

Furthermore, the heat dissipation plate 420 of the heat dissipationmodule 400 is located between the projection lens 300 and the thirdportion 416 of the heat pipe 410 and on the bottom of the optical engine200. Namely, the heat pipe 410 is far away from the projection lens 300to prevent the influence on the optical performance due to projectionlens 300 being heated by the hot air surrounding the heat pipe 410. Theheat dissipation plate 420 is connected with the bottom of the opticalengine 200. Based on a demand of high luminance, the green LED 230 isplaced upstream of air flow direction in favor of heat dissipation, andthe blue LED 240 which is relatively insensitive to the temperature isplaced downstream of air flow direction, thereby preventing other heatsources or optical elements from being influenced, wherein the upstreamand the downstream of the air flow direction refer to a sequence of thecold airflow flowing through a plurality of light sources of the heatingelements. Therefore, as illustrated in FIG. 1, the red LED 220 and theblue LED 240 are located at two sides of adjacent corner of the heatdissipation plate 420, and the red LED 220 and the blue LED 240 aredisposed relatively perpendicular to each other. The green LED 230 andthe red LED 220 are disposed adjacent to each other, and the green LED230 is more adjacent to the light valve 210 than the other LEDs. Inaddition, the performance of the red LED 220 can be reduced due to hightemperature, and thus, in order to improve a heat dissipation efficiencyof the red LED 220, the projection apparatus 10 may further include aheat sink 500. The heat sink 500 is connected with the red LED 220 toincrease a heat dissipation through thermal conduction method.

Additionally, in order to increase an intensity of the cold airflowthroughout the projection apparatus 10, the projection apparatus 10 mayfurther include a plurality of first fans 300 (which are schematicallyillustrated as two in FIG. 1) and a plurality of second fans (which areschematically illustrated as two in FIG. 1). The first fans 600 aredisposed inside the chassis 100 and located between the first portion412 of the heat pipe 410 and the heat dissipation plate 420. The secondfans 700 are disposed inside the chassis 100 and located between thesecond portion 414 of the heat pipe 410 and the air outlet 104. Inaddition, the second fans 700 disposed between the second portion 414 ofthe heat pipe 410 and the air outlet 104, and disposed away from theheat sources (the heating elements), such that a space is provided forthe airflow (the hot air) to gather and then be exhausted out of theprojection apparatus 10 by the second fans 700. When a part of the coldairflow enters the chassis 100 from the air inlet 102, it sequentiallyflows through the first heat dissipation fin 430/the first portion 412of the heat pipe 410, the first fans 600, the light valve 210/theprojection lens 300, the green LED 230/the red LED 220/the blue LED 240,the second heat dissipation fin 440, the second fans 700 and the airoutlet 104, thereby dissipating the heat generated by the heatingelements 210, 220, 230 and 240 from the chassis 100.

In the embodiment, as described above the length L2 of the second heatdissipation fin 440 being greater than the length L1 of the first heatdissipation fin 430, the cold airflow entering through the air inlet 102of the chassis and the first fans 300 adjacent to the light valve 210directly aims the cold airflow toward the light valve 210, withoutflowing through the first heat dissipation fin 430, such that more coldairflow may directly transmitted to the light valve 210 to reduce thetemperature of the light valve 210. In other words, the first heatdissipation fin 430 is not disposed between the air inlet 102 and thefirst fans 600 which are adjacent to the light valve 210. In addition, anormal line of an active surface (a surface with a micro-lens) of thelight valve 210 is perpendicular to the projection direction D3 of theprojection lens.

As illustrated in FIG. 2, a width W1 of the first heat dissipation fin430 is greater than a width W2 of the second heat dissipation fin 440.In addition, a volume of the second heat dissipation fin 440 is greaterthan a volume of the first heat dissipation fin 430, and thus, thesecond heat dissipation fin 440 is capable of dissipating more heat fromthe chassis 100 than the first heat dissipation fin 430. Therefore, thecold airflow flowing through the first heat dissipation fin 430, reducesthe heat from the projection lens 300 located in downstream of theairflow, and do not affect the optical performance of the projectionlens 300.

Based on the above, the embodiments of the invention can achieve atleast one of the following advantages or effects. In this design of theheat dissipation module of the invention, the length of the second heatdissipation fin along the extension direction of the second portion ofthe heat pipe is greater than the length of the first heat dissipationfin along the extension direction of the first portion of the heat pipe,and the first heat dissipation fin does not block the air enteringdirection towards the heat dissipation plate. Therefore, the heatgenerated by the heating elements which is disposed on the heatdissipation plate is dissipated by a thermal conduction and a thermalconvection method and the heating elements relatively adjacent to thefirst portion of the heat pipe can also directly dissipated in a thermalconvection method. In other words, the design of the heat dissipationmodule of the invention provides one more heat dissipation method ofthermal convection to achieve an efficient heat dissipation effect.Moreover, the projection apparatus using the heat dissipation module ofthe invention, can achieve an efficient dissipation effect, in additionit may effectively reduce the space consumption in the projectionapparatus, reduce volume and noise of the projection apparatus becauseall the heating elements are disposed on the heat dissipation plate,which are integrated as one heat source.

The foregoing description of the preferred embodiments of the inventionhas been presented for purposes of illustration and description. It isnot intended to be exhaustive or to limit the invention to the preciseform or to exemplary embodiments disclosed. Accordingly, the foregoingdescription should be regarded as illustrative rather than restrictive.Obviously, many modifications and variations will be apparent topractitioners skilled in this art. The embodiments are chosen anddescribed in order to best explain the principles of the invention andits best mode practical application, thereby to enable persons skilledin the art to understand the invention for various embodiments and withvarious modifications as are suited to the particular use orimplementation contemplated. It is intended that the scope of theinvention be defined by the claims appended hereto and their equivalentsin which all terms are meant in their broadest reasonable sense unlessotherwise indicated. Therefore, the term “the invention”, “the presentinvention” or the like does not necessarily limit the claim scope to aspecific embodiment, and the reference to particularly preferredexemplary embodiments of the invention does not imply a limitation onthe invention, and no such limitation is to be inferred. The inventionis limited only by the spirit and scope of the appended claims. Theabstract of the disclosure is provided to comply with the rulesrequiring an abstract, which will allow a searcher to quickly ascertainthe subject matter of the technical disclosure of any patent issued fromthis disclosure. It is submitted with the understanding that it will notbe used to interpret or limit the scope or meaning of the claims. Anyadvantages and benefits described may not apply to all embodiments ofthe invention. It should be appreciated that variations may be made inthe embodiments described by persons skilled in the art withoutdeparting from the scope of the invention as defined by the followingclaims. Moreover, no element and component in the disclosure is intendedto be dedicated to the public regardless of whether the element orcomponent is explicitly recited in the following claims.

What is claimed is:
 1. A heat dissipation module for dissipating heatfrom a plurality of heating elements, comprising; a heat pipe; adissipation plate; a first heat dissipation fin; and a second heatdissipation fin; wherein the heat pipe comprises a first portion, asecond portion and a third portion connected with the first and thesecond portions, wherein the first portion and the second portion aredisposed in parallel to each other; the third portion of the heat pipeand the heating elements are connected to the heat dissipation plate;the first portion of the heat pipe passes through the first heatdissipation fin; the second portion of the heat pipe passes through thesecond heat dissipation fin, wherein the heat generated by the heatingelements is dissipated by the heat dissipation plate, the first heatdissipation fin and the second heat dissipation fin in a thermalconduction method and a thermal convection method.
 2. The heatdissipation module according to claim 1, wherein the third portion ofthe heat pipe further comprises; a contact portion; a first connectionportion; and a second connection portion; wherein the contact portioncontacts the heat dissipation plate and is connected with the firstconnection portion and the second connection portion, the firstconnection portion is connected with the first portion and the contactportion of the heat pipe, and the second connection portion is connectedwith the second portion and the contact portion of the heat pipe.
 3. Theheat dissipation module according to claim 1, wherein a width of thefirst heat dissipation fin is greater than a width of the second heatdissipation fin.
 4. The heat dissipation module according to claim 1,wherein a volume of the second heat dissipation fin is greater than avolume of the first heat dissipation fin.
 5. The heat dissipation moduleaccording to claim 1, wherein the heat dissipation plate is relativelyadjacent to the second portion of the heat pipe.
 6. The heat dissipationmodule according to claim 1, wherein a length of the second heatdissipation fin along an extension direction of the second portion isgreater than a length of the first heat dissipation fin along anextension direction of the first portion, an air entering direction of acold airflow is not in parallel to the extension direction of the firstportion, and the first heat dissipation fin does not block the heatdissipation plate in the air entering direction.
 7. A projectionapparatus, comprising: a chassis, having an air inlet and an air outlet;an optical engine, disposed inside the chassis and comprises a pluralityof heating elements; a projection lens, disposed inside the chassis andconnected with the optical engine; and a heat dissipation module,disposed inside the chassis and comprises: a heat pipe; a dissipationplate; a first heat dissipation fin; and a second heat dissipation fin;wherein the heat pipe comprises a first portion, a second portion and athird portion connected with the first and the second portions, whereinthe first portion and the second portion are disposed in parallel toeach other; the third portion of the heat pipe and the heating elementsare connected to the heat dissipation plate; the first portion of theheat pipe passes through the first heat dissipation fin; the secondportion of the heat pipe passes through the second heat dissipation fin,wherein the heat generated by the heating elements is dissipated by theheat dissipation plate, the first heat dissipation fin and the secondheat dissipation fin in a thermal conduction method and a thermalconvection method.
 8. The projection apparatus according to claim 7,wherein the heating elements comprise: a plurality of light sources,disposed at one side of the heat dissipation plate and adjacent to thesecond portion of the heat pipe and employed to emit an illuminationbeam; and a light valve, disposed at the other side of the heatdissipation plate and adjacent to the first portion of the heat pipe,wherein the light valve is located on a transmission path of theillumination beam, and employed to convert the illumination beam into animage beam.
 9. The projection apparatus according to claim 8, wherein anormal line of an active surface of the light valve is perpendicular toa projection direction of the projection lens.
 10. The projectionapparatus according to claim 8, wherein the light sources comprise a redlight-emitting diodes (LED), a green LED and a blue LED, the red LED andthe blue LED are located at two sides of a corner of the heatdissipation plate, the green LED and the red LED are disposed adjacentto each other, and the green LED is relatively adjacent to the lightvalve.
 11. The projection apparatus according to claim 10, furthercomprising: a heat sink, connected with the red LED.
 12. The projectionapparatus according to claim 7, wherein the third portion of the heatpipe comprises a contact portion, a first connection portion and asecond connection portion, the contact portion contacts the heatdissipation plate and is connected with the first connection portion andthe second connection portion, the first connection portion is connectedwith the first portion and the contact portion of the heat pipe, and thesecond connection portion is connected with the second portion and thecontact portion of the heat pipe.
 13. The projection apparatus accordingto claim 7, wherein a width of the first heat dissipation fin is greaterthan a width of the second heat dissipation fin.
 14. The projectionapparatus according to claim 7, wherein a volume of the second heatdissipation fin is greater than a volume of the first heat dissipationfin.
 15. The projection apparatus according to claim 7, wherein the heatdissipation plate is relatively adjacent to the second portion of theheat pipe.
 16. The projection apparatus according to claim 7, whereinthe heat dissipation plate is located between the projection lens andthe third portion of the heat pipe.
 17. The projection apparatusaccording to claim 7, wherein an air entering direction of the air inletand an air exiting direction of the air outlet are not in parallel to aprojection direction of the projection lens.
 18. The projectionapparatus according to claim 7, further comprising: a plurality of firstfans, disposed inside the chassis and located between the first portionof the heat pipe and the heat dissipation plate; and a plurality ofsecond fans, disposed inside the chassis and located between the secondportion of the heat pipe and the air outlet.
 19. The projectionapparatus according to claim 18, wherein the first heat dissipation finis not between the air inlet and the first fans adjacent to the lightvalve.